As the pace of life gets faster, people pay more attention to health problems.Researchers at Tufts University’s engineering College have developed a new radio frequency system that can read sensor data and transmit it from a human tooth to a card reader. In the system, passive RFID tags are attached to the teeth, and a sensor is built in to respond when the sensor detects sugar or sodium. The tag transmits data to the card reader via a 400 MHz RFID signal and then modifies the status information based on the data. The technique not only identifies the amount of a particular nutrient or chemical, but also how the body responds to changes in saliva.
The new sensor tag at Tufts University consists of three layers. The central layer is made from a porous, Silk Film or hydrogel intercalation, which the researchers call a bioreaction layer. The layer absorbs saliva nutrients and expands depending on pH or temperature fluctuations. Two outer layers are used for wireless transmission, and each outer layer is a ring RF antenna. When a specific nutrient (such as glucose) is detected, the central sensor layer expands, the two antennas are slightly separated and the response amplitude and resonant frequency are changed. When the reader detects a change in status, the software can determine the presence of certain nutrients or chemicals.
Omenetto said the system was designed to allow medical practitioners or users to know the nutritional intake. For example, diabetics can attach RFID tags to their teeth, and then use a specialized reader to know the amount of glucose ingested at a given time. Labels can also be used in people who have eating disorders or eating restrictions. The user needs to place the card reader about one centimeter from the label to ensure reliable reading.
In the future, labels will add a variety of sensor layers to identify more types of chemicals or nutrients or the body’s own state.